From the past, the digitization of television broadcast has been promoted in Japan and terrestrial digital broadcast, BS digital broadcast, and the like are widely diffused. In addition, the digital television broadcast such as terrestrial digital broadcast realizes not only broadcast of AV content corresponding to so-called television programs but also so-called data content. Using data content, display of information related to a television program being broadcast (AV content), display of information that is not related to a television program being broadcast (announcement of another television program, news, weather report, traffic information, etc.), and execution of applications that interlock with a television program being broadcast (AV content) are enabled (see, for example, Patent Literature 1).
It should be noted that the broadcast of data content in Japan is realized by securing a band for data broadcast in a broadcast band for digital television broadcast in advance at a time of digitizing television broadcast, and broadcasting data content using this band.
Incidentally, in the digital television broadcast in the United States, one corresponding to the data broadcast in the digital television broadcast in Japan has not been realized. In other words, the broadcast band in the current digital television broadcast in the United States is occupied by a video band, an audio band, and a control information band as shown in FIG. 1A, and a band for broadcasting data content is not provided. Therefore, to secure a band for broadcasting data content in the limited broadcast band of the digital television broadcast, the video band and the audio band are necessary to be reduced in size as shown in FIG. 1B.